a) Field of the Invention
The present invention relates to switches, and in particular to high voltage sphere-gap discharge switches which operate by means of the generation of spark discharge.
b) Description of Related Art
Japanese Laying-open Patent Gazette No. S 63-66878 discloses a construction which employs a trigger electrode in addition to a pair of opposing electrodes, and in which a gas medium is supplied into and circulated within the discharged space. However, this construction requires an auxiliary circuit for the trigger, and the construction of the device is complicated.
Japanese Laying-open Patent Gazette No. S 58-35887 discloses a starting gap device in which a separate projection which can be extended and retracted is attached to one of a pair of sphere electrodes. However, the voltage in this device is in the region several hundred kilovolts and thus there is a lack of operational reproducibility, and moreover long term operation is problematical since consumption of the electrodes is high.